Good point. We know that large shifts in mass, like huge landslides caused by earthquakes, can measurably affect earth's rotation. What happens when we start us

Good point. We know that large shifts in mass, like huge landslides caused by earthquakes, can measurably affect earth's rotation. What happens when we start using multi-gigaton masses for energy storage -- that are within a couple orders of magnitude of those landslides -- in a cyclic pattern? I wonder if we could even get resonant effects.